Building a Betting App 101: How to Integrate a Sports Odds API (Step-by-Step Tutorial)

Developers looking to build betting apps, odds comparison tools, or sports dashboards need reliable real-time data. In this tutorial, we’ll walk through how to integrate a sports betting API into a simple app, showing you step by step how to fetch and display odds.

We’ll use Odds-API.io as our example API. With coverage from 250+ bookmakers, real-time updates, and player props data, it’s an ideal choice for building modern betting applications.

Prerequisites

Basic programming knowledge (JavaScript or Python)
An API key from Odds-API.io
A local development environment

Step 1 – Get Your API Key

Step 2 – Fetch Events

Let’s fetch football events from the API.

JavaScript Example:

import fetch from 'node-fetch';

const API_KEY = 'YOUR_API_KEY';

async function getEvents() {
  const res = await fetch(`https://api.odds-api.io/v3/events?apiKey=${API_KEY}&sport=football`);
  const events = await res.json();
  console.log(events.slice(0, 3));
}

getEvents();

This returns upcoming football matches, including IDs, teams, leagues, and status.

Step 3 – Fetch Odds for a Game

Once you have an event ID, you can pull real-time odds from selected bookmakers.

Example:

async function getOdds(eventId) {
  const bookmakers = 'Bet365,Unibet';
  const res = await fetch(`https://api.odds-api.io/v3/odds?apiKey=${API_KEY}&eventId=${eventId}&bookmakers=${bookmakers}`);
  const odds = await res.json();
  console.log(JSON.stringify(odds, null, 2));
}

getOdds(123456); // Replace with real event ID

This returns structured odds from multiple bookmakers for the same event.

Step 4 – Display the Data

For a quick demo, print the odds into a simple HTML table.

<table border="1">
  <tr>
    <th>Bookmaker</th>
    <th>Home</th>
    <th>Draw</th>
    <th>Away</th>
  </tr>
  <tr>
    <td>Bet365</td>
    <td>1.80</td>
    <td>3.40</td>
    <td>4.20</td>
  </tr>
  <tr>
    <td>Unibet</td>
    <td>1.78</td>
    <td>3.35</td>
    <td>4.25</td>
  </tr>
</table>

Step 5 – Add Real-Time Updates

For live betting, refresh odds every few seconds.

setInterval(() => {
  getOdds(123456);
}, 5000); // refresh every 5 seconds

Odds-API.io supports high-frequency updates with near-zero latency, making this setup viable for in-play betting apps.

Step 6 – Extend the App

Ideas to expand your betting app:

Add player props odds for sports like NBA or NFL
Include multiple sports (football, basketball, tennis, esports)
Create alerts when odds change significantly
Store odds in a database for historical analysis

Conclusion

Integrating a sports odds API into your app is straightforward. In under an hour, you can fetch live data from multiple bookmakers and display it in a working betting dashboard.

With Odds-API.io’s 250+ bookmakers, low latency, and strong props coverage, developers can build apps that compete at the highest level.

👉 Start building today: Get your free API key and connect live odds in minutes.